Jennifer Love Hewitt
Ghost Whisperer star was mortified in 2007 after unflattering photos of her in a black bikini showed up online—and on every newsstand—specifically focusing on her less-than-toned backside. She decried the coverage (Hewitt was still only a size 2, after all) but employed trainer Stevie Sant'Angelo to tone up. She lost 18 pounds before her 30th birthday last year by sticking to a 1,250- to 1,500-calorie-per-day diet that was heavy on fruits, veggies, and protein, and light on processed foods. A sample breakfast included two servings of mixed fruit and yogurt and she was allowed to have snacks throughout the day. One rule to maintain energy: No whole grains after 3 p.m.